  bezout - Bezout equation for polynomials or integers
  clean - cleans matrices (round to zero small entries)
  cmndred - common denominator form
  coeff - coefficients of matrix polynomial
  coffg - inverse of polynomial matrix
  colcompr - column compression of polynomial matrix
  degree - degree of polynomial matrix
  denom - denominator
  derivat - rational matrix derivative
  determ - determinant of polynomial matrix
  detr - polynomial determinant
  diophant - diophantine (Bezout) equation
  factors - numeric real factorization
  gcd - gcd calculation
  hermit - Hermite form
  horner - polynomial/rational evaluation
  hrmt - gcd of polynomials
  htrianr - triangularization of polynomial matrix
  invr - inversion of (rational) matrix
  lcm - least common multiple
  lcmdiag - least common multiple diagonal factorization
  ldiv - polynomial matrix long division
  numer - numerator
  pdiv - polynomial division
  pol2des - polynomial matrix to descriptor form
  pol2str - polynomial to string conversion
  polfact - minimal factors
  residu - residue
  roots - roots of polynomials
  routh_t - Routh's table
  rowcompr - row compression of polynomial matrix
  sfact - discrete time spectral factorization
  simp - rational simplification
  simp_mode - toggle rational simplification
  sylm - Sylvester matrix
  systmat - system matrix